The U.S. base, which is adjacent to Manas International Airport outside Bishkek, was established in late 2001 to support the international military campaign in Afghanistan. It functions as an interim point for troops going into or out of Afghanistan and as a home for the tanker planes that refuel warplanes in flight.
The Manas base has been the subject of a contentious dispute between the United States and its host nation.
In 2009, the U.S. reached an agreement with the Kyrgyz government to use it in return for $60 million a year. But the lease runs out in June 2014, and the U.S. wants to keep the base longer to aid in the withdrawal of troops from Afghanistan. Kyrgyzstan is reluctant to extend the lease.
On Monday, a Boeing 747 cargo plane crashed just after takeoff from the U.S. military base in Bagram, Afghanistan, killing all seven people aboard. The National Transportation Safety Board is investigating that crash since it was on the Bagram air base.
AP writers Jim Heintz in Moscow and Robert Burns in Washington, D.C., contributed to this report.